三株鸭源H7N2亚型禽流感病毒的遗传进化分析及其致病性研究  

Phylogenetic analysis and pathogenicity evaluation of three duck-orgin H7N2 avian influenza viruses

作　　者：李梅 尹馨 侯玉杰[1] 邓国华[1] 崔鹏飞[1] 房敬真 施建忠[1] 陈化兰[1] LI Mei;YIN Xin;HOU Yu-jie;DENG Guo-hua;CUI Peng-fei;FANG Jing-zhen;SHI Jian-zhong;CHEN Hua-lan(Influenza Laboratory of the Ministry of Agricultural,State Key Laboratory of Veterinary Biotechnology,Harbin Veterinary Research Institute,Chinese Academy of Agricultural Sciences,Harbin 150069,China)

机构地区：[1]中国农业科学院哈尔滨兽医研究所兽医生物技术国家重点实验室/农业部动物流感重点实验室,黑龙江哈尔滨150069

出　　处：《中国预防兽医学报》2019年第12期1193-1198,共6页Chinese Journal of Preventive Veterinary Medicine

基　　金：国家重点研发项目(2016YFD0500201)。

摘　　要：为了解我国H7N2亚型禽流感病毒(AIV)的进化及评估病毒对动物的致病性风险,本研究对2012年~2015年从浙江和湖南省活禽市场分离到的3株鸭源H7N2亚型AIV进行了遗传演化分析,并研究了其对家禽和哺乳动物小鼠的致病性。基因序列分析显示,3株病毒均是多个亚型AIV的重组体,表明不同来源病毒具有明显的基因多样性,可分为3个基因型。鸡的感染性试验结果显示,滴鼻感染3 d后,3株病毒感染组鸡的喉头、泄殖腔均有部分排毒,其中仅DK/ZJ/S3192/2012分离株可在鸡的脏器中检测到病毒,提示鸭源性H7N2亚型AIV在鸡体内仅具有有限的复制能力;鸭的感染性试验结果显示,3株病毒在鸭的脏器内均有不同程度的复制;小鼠的感染性试验结果表明,3株病毒均可以在没有预先适应的小鼠肺和鼻甲中高效复制,其中DK/HuN/S1515/2014分离株可在被迫杀的3只小鼠中的1只小鼠的脑组织中复制。以上结果表明3株H7N2亚型AIV对家禽和小鼠均呈现低致病力。本研究为H7N2 AIV的持续监测提供了数据支持,并且评估了其可能导致人类感染的风险。To investigate the evolution of H7N2 avian influenza viruses(AIVs)and their pathogenicity risk to animals,we performed the sequences analysis of the virus genes and pathogenicity evaluation of three duck-orgin H7N2 AIVs,which were isolated from the live poultry market in Zhejiang and Hunan province between 2012 and 2015,in poultry and mice.Sequences analysis revealed that all three viruses were recombinanted of multiple subtypes of AIVs with distinctgenetic diversity,and could be categorized into three genotypes.When three groups of SPF chickens were inoculated with these H7N2 viruses,respectively,some birds from each infected group shed virus from throat and cloaca at 3 days post infection,and the virus DK/ZJ/S3192/2012 could be detected in some organs of the infected chickens,suggesting that duck-orgin H7N2 had limited replicationability in chickens.Duck infection experiments showed that the three viruses had different replication levels in ducks.The pathogenicity in mice indicated that all three viruses could be efficiently replicated in lungs and turbinate in mice without prior adaptation,and DK/HuN/S1515/2014 could be detected in the brain of one of three infected mice.These results indicated that three H7N2 AIV sexhibited low pathogenicity in poultry and mice.This study provided data support for continiously monitoring the evolution of H7N2 viruses and evaluate their potential to cause human infections.

关 键 词：H7N2 禽流感病毒 遗传进化 致病性 

分 类 号：S852.65[农业科学—基础兽医学]